As shown in FIG. 1, the conventional battery set 200 of the scooter is retained on a folding device 100 by means of two lugs 210, which are retained by a support frame 94. The support frame 94 is fastened with the folding device 100. The battery set 200 is susceptible to being detached from the support frame 94.
As shown in FIG. 2, the conventional battery set 200 is retained by a support frame 94 in such a manner that the eyes 95 of the support frame 94 catch the hooks 93 which are fastened with the lashing straps 91. The battery set 200 can not be handily detached to facilitate the replacing of batteries. In addition, such a retaining means as described above undermines the over-all esthetic effect of the scooter.